Most users probably never adjust it. Within the System > Power & battery menu ... performance.” (Some PC and board makers use different language, but the settings are essentially the same.) ...
Adjust your power settings to high performance or ultimate performance to ensure maximum FPS and full enjoyment of your gaming machine, accessible through Power & Sleep settings in the Start menu.
This helps prevent screen burn-in, and keeps your computer from using more power than it needs ... Once you close this window, your settings will be saved. You've now set your sleep timer.